What Driving Patterns Signal Intoxication?

Posted By Law Offices of Mark Girdner || 18-Jul-2017

How can law enforcement tell that a driver is intoxicated without pulling
them over? Officers can’t just pull you over at random without a
reason to check your intoxication levels; they need to have a reason or
suspicion that a crime may have been committed. However, officers can
usually gain this “reasonable suspicion” by observing driving
behaviors. Officers will often spot one of these erratic behaviors and
then follow this individual for a little while to see if they continue
to show more of them. Once they see enough to create this reasonable suspicion,
they’ll make the stop and proceed with further investigations.

Here is a list of just a few of the behaviors that officers will look for
to determine if an individual is intoxicated:

Weaving: Drivers who are intoxicated have a difficult time staying in their line
and driving in a straight line. Rather, they will frequently weave from
side to side in their lane while making subtle corrections.

Crossing & straddling lane lines: While some drivers can stay within their lane lines, those who are even
more intoxicated may find they’re constantly hugging lane lines
or even straddling them while going down the road, an even bigger giveaway
that a driver could be intoxicated.

Swerving: Drivers who are intoxicated may be unable to stay in a lane at all and
will regularly swerve from side to side, often without signaling. Officers
who spot this will usually make the traffic stop almost immediately.

Misjudging stopping distances: Drunk drivers have trouble braking evenly. They’ll either brake
far too early and have to continually roll forward, or they’ll stop
too late and have to slam on their brakes to avoid hitting another car.
They may also stop in a jerky manner.

Widely varying speed: Drunk drivers have a hard time maintaining an even and constant speed.
Continually accelerating and decelerating is a pretty big giveaway of
intoxication.

Driving too slow: Drivers who are intoxicated may try to fool everyone by driving slower
so they can stay in control and not show other signals, but they’ll
often go well under the speed limit, blocking traffic and signaling their
own drunkenness.

Slow to respond to traffic signals: If a driver doesn’t notice a light has turned green and sits there
for several seconds after, they’re either intoxicated or on their
phone, both punishable offenses.

Lack of headlights: Drivers who are drunk often forget to turn on their lights, though this
is becoming rarer with “auto” headlight settings.

Following too closely (tailgating): Studies have shown drunk drivers have a tendency to tailgate those in
front of them, which is not a good thing when you consider they also tend
to brake slower.